Move non-release-critical jobs to quantal slaves.

This switches any jobs which previously used the precise node label
to quantal instead, but only if they're not gating core OpenStack
projects. All infrastructure projects have already been running
their jobs on quantal slaves successfully for the past week. The
remaining precise jobs will wait until after the Grizzly release.

Change-Id: I4f827afe900ea4b44f7ce38bdf0cd8d9d9034794
Merge "Move non-release-critical jobs to quantal slaves."